Stable PbS colloidal quantum dot inks enable scalable preparation of infrared solar cells by blade coating

Stable PbS colloidal quantum dot inks enable scalable preparation of infrared solar cells by blade coating

by Staff Writers

Wuhan, China (SPX) Nov 08, 2023

The goal of peak carbon dioxide emissions and achieve carbon neutrality is a major strategic decision made by China. Developing clean and low-cost solar photovoltaic power is an important strategy and technical guarantee to realize it.

The theoretical research shows that the tandem device consisting of a 1.55 eV perovskite top-cell and 1.0 eV PbS quantum dots (QDs) bottom-cell can achieve an ideal power conversion efficiency (PCE) of 43%, which is much higher than the 33% single junction limit. Thus, 1.0 eV QD near-infrared solar cells (NIRSCs) show high potential in next-generation photovoltaics and tandem solar cells.

Researchers led by Prof. Haisheng Song at Huazhong University of Science and Technology (HUST), China, are interested in next generation photovoltaic technology such as QDs NIRSCs. Up to now, such devices suffer from the absence of scalable preparation method for device fabrication.

Thus, they developed a mixed solvent system from dimethylformamide (DMF) and butylamine (BTA) according to Lewis acid-base theory and DLVO theory. This system can maintain the stability of QD inks and is compatible with the large-scale blade coating process.

The stability time of QD ink based on this system could stay as fresh one exceeding 7 hours, and 100 cm2 uniform QD films is successfully obtained by blade coating. The large area QD film based device achieves an average PCE of 11.14% and an 800 nm-filtered PCE of 4.28%, which are the top values reached in reported research literature to date for the blade coating method. The work entitled “Stable PbS colloidal quantum dot inks enable blade-coating infrared solar cells” was published on Frontiers of Optoelectronics (published on Oct. 26, 2023).

Research Report:Stable PbS colloidal quantum dot inks enable blade-coating infrared solar cells